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#
# Bug #34513359 Cost for field=dependent_subquery not included
#
CREATE TABLE num (n INT);
INSERT INTO num VALUES (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
CREATE TABLE t1 (a INT PRIMARY KEY, b INT);
INSERT INTO t1 SELECT n,n FROM num;
ANALYZE TABLE t1;
Table Op Msg_type Msg_text
test.t1 analyze status OK
EXPLAIN FORMAT=TREE SELECT * FROM t1 x1
WHERE x1.b = (SELECT MAX(b) FROM t1 x2 WHERE x2.a>x1.a);
EXPLAIN
-> Filter: (x1.b = (select #2)) (cost=2.38..23.8 rows=10)
-> Table scan on x1 (cost=0.025..0.25 rows=10)
-> Select #2 (subquery in condition; dependent)
-> Aggregate: max(x2.b) (cost=2.25..2.25 rows=1)
-> Filter: (x2.a > x1.a) (cost=0.125..1.25 rows=10)
-> Table scan on x2 (cost=0.025..0.25 rows=10)
Warnings:
Note 1276 Field or reference 'test.x1.a' of SELECT #2 was resolved in SELECT #1
EXPLAIN FORMAT=TREE SELECT * FROM t1 x1
WHERE x1.b IN (SELECT MAX(b) FROM t1 x2 WHERE x2.a>x1.a);
EXPLAIN
-> Filter: <in_optimizer>(x1.b,<exists>(select #2)) (cost=2.48..24.8 rows=10)
-> Table scan on x1 (cost=0.025..0.25 rows=10)
-> Select #2 (subquery in condition; dependent)
-> Filter: (<cache>(x1.b) = <ref_null_helper>(max(x2.b))) (cost=2.35..2.35 rows=1)
-> Aggregate: max(x2.b) (cost=2.25..2.25 rows=1)
-> Filter: (x2.a > x1.a) (cost=0.125..1.25 rows=10)
-> Table scan on x2 (cost=0.025..0.25 rows=10)
Warnings:
Note 1276 Field or reference 'test.x1.a' of SELECT #2 was resolved in SELECT #1
EXPLAIN FORMAT=TREE SELECT * FROM t1 x1
WHERE x1.b = (SELECT MAX(b) FROM t1 x2 WHERE x2.a>5);
EXPLAIN
-> Filter: (x1.b = (select #2)) (cost=1.19..2.31 rows=10)
-> Table scan on x1 (cost=0.025..0.25 rows=10)
-> Select #2 (subquery in condition; run only once)
-> Aggregate: max(x2.b) (cost=1.06..1.06 rows=1)
-> Index range scan on x2 using PRIMARY over (5 < a) (cost=0.165..0.661 rows=4)
EXPLAIN FORMAT=TREE SELECT * FROM t1 x1
WHERE x1.b IN (SELECT MAX(b) FROM t1 x2 WHERE x2.a>5);
EXPLAIN
-> Filter: <in_optimizer>(x1.b,x1.b in (select #2)) (cost=1.49..3.51 rows=10)
-> Table scan on x1 (cost=0.025..0.25 rows=10)
-> Select #2 (subquery in condition; run only once)
-> Filter: ((x1.b = `<materialized_subquery>`.`MAX(b)`)) (cost=1.26..1.26 rows=1)
-> Limit: 1 row(s) (cost=1.16..1.16 rows=1)
-> Index lookup on <materialized_subquery> using <auto_distinct_key> (MAX(b)=x1.b)
-> Materialize with deduplication (cost=1.16..1.16 rows=1)
-> Aggregate: max(x2.b) (cost=1.06..1.06 rows=1)
-> Index range scan on x2 using PRIMARY over (5 < a) (cost=0.165..0.661 rows=4)
EXPLAIN FORMAT=TREE SELECT * FROM t1 x1
WHERE x1.b = (SELECT MAX(b) FROM t1 x2 WHERE x2.a>10*rand(0));
EXPLAIN
-> Filter: (x1.b = (select #2)) (cost=2.38..23.8 rows=10)
-> Table scan on x1 (cost=0.025..0.25 rows=10)
-> Select #2 (subquery in condition; uncacheable)
-> Aggregate: max(x2.b) (cost=2.25..2.25 rows=1)
-> Filter: (x2.a > (10 * rand(0))) (cost=0.125..1.25 rows=10)
-> Table scan on x2 (cost=0.025..0.25 rows=10)
EXPLAIN FORMAT=TREE SELECT * FROM t1 x1
WHERE x1.b IN (SELECT MAX(b) FROM t1 x2 WHERE x2.a>10*rand(0));
EXPLAIN
-> Filter: <in_optimizer>(x1.b,<exists>(select #2)) (cost=2.48..24.8 rows=10)
-> Table scan on x1 (cost=0.025..0.25 rows=10)
-> Select #2 (subquery in condition; dependent)
-> Filter: (<cache>(x1.b) = <ref_null_helper>(max(x2.b))) (cost=2.35..2.35 rows=1)
-> Aggregate: max(x2.b) (cost=2.25..2.25 rows=1)
-> Filter: (x2.a > (10 * rand(0))) (cost=0.125..1.25 rows=10)
-> Table scan on x2 (cost=0.025..0.25 rows=10)
EXPLAIN FORMAT=TREE SELECT SUM(x1.a) s FROM t1 x1
GROUP BY x1.b HAVING s>(SELECT MAX(x2.a) FROM t1 x2);
EXPLAIN
-> Filter: (s > (select #2)) (cost=6.24..7.14 rows=3.16)
-> Group aggregate: sum(x1.a) (cost=4.89..5.57 rows=3.16)
-> Sort: x1.b (cost=4.57..4.57 rows=10)
-> Table scan on x1 (cost=0.025..0.25 rows=10)
-> Select #2 (subquery in condition; run only once)
-> Aggregate: max(x2.a) (cost=1.25..1.25 rows=1)
-> Table scan on x2 (cost=0.025..0.25 rows=10)
EXPLAIN FORMAT=TREE SELECT SUM(x1.a) s FROM t1 x1
GROUP BY x1.b HAVING s>(SELECT MAX(x2.a+RAND(0)) FROM t1 x2);
EXPLAIN
-> Filter: (s > (select #2)) (cost=6.24..9.84 rows=3.16)
-> Group aggregate: sum(x1.a) (cost=4.89..5.57 rows=3.16)
-> Sort: x1.b (cost=4.57..4.57 rows=10)
-> Table scan on x1 (cost=0.025..0.25 rows=10)
-> Select #2 (subquery in condition; uncacheable)
-> Aggregate: max((x2.a + rand(0))) (cost=1.25..1.25 rows=1)
-> Table scan on x2 (cost=0.025..0.25 rows=10)
-> Select #2 (subquery in projection; uncacheable)
-> Aggregate: max((x2.a + rand(0))) (cost=1.25..1.25 rows=1)
-> Table scan on x2 (cost=0.025..0.25 rows=10)
DROP TABLE num,t1;
#
# Bug#34114563 EXPLAIN ANALYZE: Use at least one significant digit for average
# of actual rows
#
CREATE TABLE num10 (n INT);
INSERT INTO num10 VALUES (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
CREATE TABLE t1(
a INT,
b INT,
c INT,
d INT,
e INT,
f INT,
g INT,
h INT,
KEY(d)
);
INSERT INTO t1
SELECT n%17, n% 19, n, n, n, n, n, n
FROM (SELECT d1.n+d2.n*10+d3.n*100 n FROM num10 d1, num10 d2, num10 d3) num1000;
ANALYZE TABLE t1 UPDATE HISTOGRAM ON a,b,c,d,e,f,g,h;
Table Op Msg_type Msg_text
test.t1 histogram status Histogram statistics created for column 'a'.
test.t1 histogram status Histogram statistics created for column 'b'.
test.t1 histogram status Histogram statistics created for column 'c'.
test.t1 histogram status Histogram statistics created for column 'd'.
test.t1 histogram status Histogram statistics created for column 'e'.
test.t1 histogram status Histogram statistics created for column 'f'.
test.t1 histogram status Histogram statistics created for column 'g'.
test.t1 histogram status Histogram statistics created for column 'h'.
ANALYZE TABLE t1;
Table Op Msg_type Msg_text
test.t1 analyze status OK
EXPLAIN FORMAT=TREE SELECT * FROM t1 WHERE c<720;
EXPLAIN
-> Filter: (t1.c < 720) (cost=0.141..102 rows=720)
-> Table scan on t1 (cost=0.0015..1.5 rows=1000)
EXPLAIN FORMAT=TREE SELECT * FROM t1 x1, t1 x2, t1 x3 WHERE x1.c<721 AND x2.c<900;
EXPLAIN
-> Nested loop inner join (cost=174..1.02e+6 rows=649e+6)
-> Inner hash join (no condition) (cost=174..45788 rows=648900)
-> Filter: (x2.c < 900) (cost=0.113..102 rows=900)
-> Table scan on x2 (cost=0.0015..1.5 rows=1000)
-> Hash
-> Filter: (x1.c < 721) (cost=0.141..102 rows=721)
-> Table scan on x1 (cost=0.0015..1.5 rows=1000)
-> Table scan on x3 (cost=0.0015..1.5 rows=1000)
EXPLAIN ANALYZE FORMAT=TREE SELECT * FROM t1 x1, t1 x2 WHERE x1.c=x2.d AND x1.d>900 AND x2.a=x2.b;
EXPLAIN
-> Nested loop inner join (cost=11.9..69.6 rows=5.82) (actual rows=17 loops=1)
-> Index range scan on x1 using d over (900 < d) (cost=0.353..34.9 rows=99) (actual rows=99 loops=1)
-> Filter: (x2.a = x2.b) (cost=0.35..0.35 rows=0.0588) (actual rows=0.172 loops=99)
-> Index lookup on x2 using d (d=x1.c) (cost=0.25..0.25 rows=1) (actual rows=1 loops=99)
EXPLAIN FORMAT=TREE SELECT * FROM t1 x1, t1 x2, t1 x3 WHERE x1.c<921 AND x2.c<900;
EXPLAIN
-> Nested loop inner join (cost=192..1.3e+6 rows=829e+6)
-> Inner hash join (no condition) (cost=192..58408 rows=828900)
-> Filter: (x1.c < 921) (cost=0.11..102 rows=921)
-> Table scan on x1 (cost=0.0015..1.5 rows=1000)
-> Hash
-> Filter: (x2.c < 900) (cost=0.113..102 rows=900)
-> Table scan on x2 (cost=0.0015..1.5 rows=1000)
-> Table scan on x3 (cost=0.0015..1.5 rows=1000)
EXPLAIN FORMAT=TREE SELECT * FROM t1 WHERE e=0 AND c=0;
EXPLAIN
-> Filter: ((t1.e = 0) and (t1.c = 0)) (rows=0.001)
-> Table scan on t1 (rows=1000)
EXPLAIN FORMAT=TREE SELECT * FROM t1 WHERE e=0 AND c=0 AND f<999;
EXPLAIN
-> Filter: ((t1.e = 0) and (t1.c = 0) and (t1.f < 999)) (rows=999e-6)
-> Table scan on t1 (rows=1000)
EXPLAIN FORMAT=TREE SELECT * FROM t1 x1, t1 x2 LIMIT 999999;
EXPLAIN
-> Limit: 999999 row(s) (rows=999999)
-> Nested loop inner join (rows=1e+6)
-> Table scan on x1 (rows=1000)
-> Table scan on x2 (rows=1000)
EXPLAIN FORMAT=TREE SELECT * FROM t1 WHERE d=0 AND c=0 AND e=0 AND f=0 AND g=0;
EXPLAIN
-> Filter: ((t1.c = 0) and (t1.e = 0) and (t1.f = 0) and (t1.g = 0)) (rows=1e-12)
-> Index lookup on t1 using d (d=0) (rows=1)
EXPLAIN FORMAT=TREE
SELECT * FROM t1 WHERE a=0 AND b=0 AND c=0 AND e=0 AND f=0 AND g=0 AND h=0;
EXPLAIN
-> Filter: ((t1.c = 0) and (t1.e = 0) and (t1.f = 0) and (t1.g = 0) and (t1.h = 0) and (t1.b = 0) and (t1.a = 0)) (rows=0)
-> Table scan on t1 (rows=1000)
EXPLAIN FORMAT=TREE SELECT * FROM t1 x1, t1 x2, t1 x3 LIMIT 999500000;
EXPLAIN
-> Limit: 999500000 row(s) (rows=1e+9)
-> Nested loop inner join (rows=1e+9)
-> Nested loop inner join (rows=1e+6)
-> Table scan on x1 (rows=1000)
-> Table scan on x2 (rows=1000)
-> Table scan on x3 (rows=1000)
EXPLAIN FORMAT=TREE SELECT * FROM t1 x1, t1 x2, t1 x3 LIMIT 999499999;
EXPLAIN
-> Limit: 999499999 row(s) (rows=999e+6)
-> Nested loop inner join (rows=1e+9)
-> Nested loop inner join (rows=1e+6)
-> Table scan on x1 (rows=1000)
-> Table scan on x2 (rows=1000)
-> Table scan on x3 (rows=1000)
DROP TABLE num10,t1;
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